Search for: environmental-analysis
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    Pyrrole-based conductive polymer as the solid-phase extraction medium for the preconcentration of environmental pollutants in water samples followed by gas chromatography with flame ionization and mass spectrometry detection

    , Article Journal of Chromatography A ; Volume 1015, Issue 1-2 , 2003 , Pages 23-30 ; 00219673 (ISSN) Bagheri, H ; Mohammadi, A ; Sharif University of Technology
    Elsevier  2003
    A pyrrole-based polymer was synthesized and applied as a new sorbent for solid-phase extraction (SPE) of some environmental pollutants from water samples. Polypyrrole (PPy) was synthesized by chemical oxidation of the monomer in nonaqueous solution. SPE of selected phenols, pesticides, and polyaromatic hydrocarbons (PAHs) from aqueous samples were performed using 200mg PPy. The determination was subsequently carried out by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The polymer showed much higher recoveries for aromatic compounds than aliphatics. Preconcentration of sample volumes up 1l led to acceptable recoveries for aromatic and... 

    Conductive polymers as new media for solid-phase extraction: Isolation of chlorophenols from water sample

    , Article Journal of Chromatography A ; Volume 986, Issue 1 , 2003 , Pages 111-119 ; 00219673 (ISSN) Bagheri, H ; Saraji, M ; Sharif University of Technology
    Elsevier  2003
    Three different conductive polymers, poly-N-methylaniline (PNMA), polyaniline and polydiphenylamine were synthesised and used as sorbents for the solid-phase extraction of some phenolic compounds from water. The separation and determination was, subsequently, performed by gas chromatography-electron-capture and flame ionization detection. Among these easy-made polymers, PNMA gave better recovery for the extraction of the studied analytes. The capability of the PNMA to extract other non-polar compounds such as chloro- and methylbenzene, decane, decanol, cyclohexane and cyclohexanol was also studied. The polymer showed some sort of selectivity towards aromatic compounds than aliphatic.... 

    New polymeric sorbent for the solid-phase extraction of chlorophenols from water samples followed by gas chromatography-electron-capture detection

    , Article Journal of Chromatography A ; Volume 910, Issue 1 , 2001 , Pages 87-93 ; 00219673 (ISSN) Bagheri, H ; Saraji, M ; Sharif University of Technology
    A polymeric material, polyaniline, was employed as a new sorbent for solid-phase extraction (SPE) of some environmental pollutants from water samples. Chlorophenols were extracted from aqueous samples by SPE using 120 mg polyaniline and determined by gas chromatography with electron-capture detection. The acetate esters of these phenols were formed by the direct addition of acetic anhydride to the organic extractant in the presence of K2CO3. Different conditions were applied to obtain higher retaining capacity and breakthrough volumes. The results compared with those obtained by other groups. The RSD for a river water sample spiked at sub-ppb level was lower than 10% (n = 3) and detection... 

    Development of Microextraction Methods
    for the Trace Determination of Organic Compounds in Biological and Environmental Media

    , Ph.D. Dissertation Sharif University of Technology Khalilian, Faezeh (Author) ; Bagheri, Habib (Supervisor)
    The approach of this thesis is to develop and simplify robust microextraction techniques and apply these developed methods to real samples and complex matrices. Firstly, a modified solvent microextraction with back extraction method (SME/BE) combined with high performance liquid chromatography and fluorescence detection (HPLC-FD) was developed for the determination of citalopram in human plasma. Extraction process was performed in a home-made total glass vial without using a teflon ring, usually employed in SME/BE. The evaluation results demonstrated that the calibration curve showed linearity in the range of 1.0–130.0 ng/mL which covers therapeutic window and even lower amounts which is... 

    Exergy, economic, and environmental analysis of a PEM fuel cell power system to meet electrical and thermal energy needs of residential buildings

    , Article Journal of Fuel Cell Science and Technology ; Volume 9, Issue 5 , 2012 ; 1550624X (ISSN) Ashari, G. R ; Ehyaei, M. A ; Mozafari, A ; Atabi, F ; Hajidavalloo, E ; Shalbaf, S ; Sharif University of Technology
    ASME  2012
    In this paper, a Polymer Electrolyte Membrane (PEM) fuel cell power system including burner, steam reformer, heat exchanger, and water heater has been considered. A PEM fuel cell system is designed to meet the electrical, domestic hot water, heating, and cooling loads of a residential building located in Tehran. Operating conditions of the system with consideration of the electricity cost has been studied. The cost includes social cost of the environmental pollutants (e.g. CO 2, CO and NO). The results show that the maximum energy needs of the building can be met by 12 fuel cell stacks with nominal capacity of 8.5 kW. Annual average electricity cost of thissystem is equal to 0.39 US$/kWh and... 

    Comparing different scenarios for thermal enhanced oil recovery in fractured reservoirs using hybrid solar-gas steam generators, a simulation study

    , Article Society of Petroleum Engineers - SPE Europec Featured at 78th EAGE Conference and Exhibition, 30 May 2016 through 2 June 2016 ; 2016 ; 9781613994573 (ISBN) Mirzaie Yegane, M ; Bashtani, F ; Tahmasebi, A ; Ayatollahi, S ; Al Wahaibi, Y. M ; Sharif University of Technology
    Society of Petroleum Engineers  2016
    The application of the renewable energy sources, especially solar energy, for thermal enhanced oil recovery methods as an economical and environmental valuable technique has received many attractions recently. Concentrated Solar Power systems are capable of producing substantial quantities of steam by means of focused sunlight as the heat source for steam generation. This paper aims to investigate viability of using this innovative technology in fractured reservoirs to generate steam instead of using conventional steam generators. A synthetic fractured reservoir with properties similar to those of giant carbonate oil reserves in the Middle East was designed by using commercial thermal... 

    A year-round study of a photovoltaic thermal system integrated with phase change material in Shanghai using transient model

    , Article Energy Conversion and Management ; Volume 210 , 2020 Kazemian, A ; Salari, A ; Ma, T ; Sharif University of Technology
    Elsevier Ltd  2020
    In the study, the daily and monthly performance of a photovoltaic thermal system integrated with phase change material is investigated in Shanghai, China. A three-dimensional model of photovoltaic thermal system integrated with phase change material system is developed and numerically simulated. Water is considered as working fluid, and the fluid flow regime is laminar and incompressible. Both quasi-steady and transient models are compared together, and the transient model is selected because of its higher accuracy. Validation analysis is performed on the numerical model to show the reasonable agreement of current research compared to some other research. After obtaining the suitable... 

    Optimal working conditions of various city gate stations for power and hydrogen production based on energy and eco-exergy analysis

    , Article International Journal of Hydrogen Energy ; Volume 45, Issue 43 , September , 2020 , Pages 22513-22533 Kowsari, S ; Deymi Dashtebayaz, M ; Karbasi, K ; Sheikhani, H ; Sharif University of Technology
    Elsevier Ltd  2020
    In this study, the feasibility of producing power and hydrogen from the waste heat of different City Gate Stations (CGSs) is investigated to select the optimal working conditions. A thermodynamic model is developed for a proposed system combined of the CGS station, the Rankin cycle and the extended hydrogen production cycle. Initially, six CGS stations are simulated based on energy, exergy-economic and environmental analysis and then a comparative study is conducted between different stations. The results of numerical modeling show that the Mashhad-old station with 5315 kW and 31.062 ton/year has the highest amount of power and hydrogen production among other stations, respectively. It is... 

    Distilled water production with combination of solar still and thermosyphon heat pipe heat exchanger coupled with indirect water bath heater – Experimental study and thermoeconomic analysis

    , Article Applied Thermal Engineering ; Volume 176 , 2020 Rastegar, S ; Kargarsharifabad, H ; Rahbar, N ; Shafii, M. B ; Sharif University of Technology
    Elsevier Ltd  2020
    The aim of this study is to provide a solution for supplying distilled water used in indirect water bath heaters in the pressure reduction stations. A particular type of distilled water production system consists of a typical solar still and a heat pipe heat exchanger was constructed for recovering heat from the exhaust of an indirect gas heater. The system was tested under the climatic conditions of Semnan-Iran. Experimental results showed that in active type, the average daily production rate of distilled water would be 2.06 times higher than passive type. Also, in the proposed system, the average daily energy efficiency and the exergy efficiency would be 65.5% and 41% higher than the... 

    Headspace solvent microextraction as a simple and highly sensitive sample pretreatment technique for ultra trace determination of geosmin in aquatic media

    , Article Journal of Separation Science ; Volume 29, Issue 1 , 2006 , Pages 57-65 ; 16159306 (ISSN) Bagheri, H ; Salemi, A ; Sharif University of Technology
    A headspace solvent microextraction method was developed for the trace determination of geosmin, an odorant compound, in water samples. After performing the extraction by a microdrop of an organic solvent, the microdrop was introduced directly into a GC-MS injection port. One-at-the-time optimization strategy was applied to investigate and optimize some important extraction parameters such as type of solvent, drop volume, temperature, stirring rate, ionic strength, sample volume, and extraction time. The analytical data exhibited an RSD of less than 5% (n = 5), a linear calibration range of 5-900 ng/L (r2 > 0.998), and a detection limit of 0.8 and 3.3 ng/L using two different sets of... 

    Energy, economic and environmental (3E) analysis of a micro gas turbine employed for on-site combined heat and power production

    , Article Energy and Buildings ; Volume 42, Issue 2 , 2010 , Pages 259-264 ; 03787788 (ISSN) Ehyaei, M. A ; Mozafari, A ; Sharif University of Technology
    This paper studies the optimization of micro turbine application to meet the electrical, heating and cooling loads of a building by energy, economics and environmental analysis. In this study following three cases are considered: 1: A simple micro gas turbine to meet the electrical power of the building. 2: A simple micro gas turbine to meet the electrical power of the building as well as the power required by heat pump and mechanical refrigerator needed for heating, cooling and domestic hot water (DHW) systems. 3: A CHP micro gas turbine to meet the electrical power of the building as well as part of the power required by heat pump and mechanical refrigerator needed for heating, cooling and... 

    Techno-economic and environmental analysis of an integrated standalone hybrid solar hydrogen system to supply CCHP loads of a greenhouse in Iran

    , Article International Journal of Green Energy ; Volume 14, Issue 3 , 2017 , Pages 295-309 ; 15435075 (ISSN) Homayouni, F ; Roshandel, R ; Hamidi, A. A ; Sharif University of Technology
    The techno-economic and environmental performance of hybrid solar hydrogen energy systems was investigated to provide combined cooling, heating and power (CCHP) demands of a standalone greenhouse in Iran to achieve sustainable agriculture based on an optimization procedure. From the environmental point of view, by deploying hybrid energy systems, 83%, to 100% of emissions can be avoided. Also a sensitivity analysis was performed on the hybrid energy systems in order to study the effect of major parameter variation on the systems justification. It was concluded that hybrid solar systems are economically competitive with conventional systems, for high solar intensity locations with high diesel... 

    Rubberized alkali-activated slag mortar reinforced with polypropylene fibres for application in lightweight thermal insulating materials

    , Article Construction and Building Materials ; 2020 Rajaei, S ; Shoaei, P ; Shariati, M ; Ameri, F ; Musaeei, H. R ; Behforouz, B ; de Brito, J ; Sharif University of Technology
    Elsevier Ltd  2020
    Every year, about a thousand million tires reach the end of their service life, more than half of which are disposed of in landfills. The waste tire rubber has a great potential for application as aggregate phase in production of lightweight concrete/mortar. This study is aimed at evaluating the effects of using crumb rubber (CR) as fine aggregate at replacement ratios of 0–60% (by volume) in alkali-activated slag mortars. Furthermore, polypropylene fibre (PPF) was used at 0.5% and 1% of volume of the mix to enhance the properties of mortar mixes such as flexural strength and shrinkage behaviour. The compressive strength, flexural strength, water absorption, thermal conductivity, drying... 

    Membrane protected conductive polymer as micro-SPE device for the determination of triazine herbicides in aquatic media

    , Article Journal of Separation Science ; Volume 33, Issue 8 , 2010 , Pages 1132-1138 ; 16159306 (ISSN) Bagheri, H ; Khalilian, F ; Naderi, M ; Babanezhad, E ; Sharif University of Technology
    A micro-SPE technique was developed by fabricating a rather small package including a polypropylene membrane shield containing the appropriate sorbent. The package was used for the extraction of some triazine herbicides from aqueous samples. Solvent desorption was subsequently performed in a microvial and an aliquot of extractant was injected into GC-MS. Various sorbents including aniline-ortho-phenylene diamine copolymer, newly synthesized, polypyrrole, multiwall carbon nanotube, C18 and charcoal were examined as extracting media. Among them, conductive polymers exhibited better performance. Influential parameters including extraction and desorption time, desorption solvent and the ionic... 

    Implementing a superhydrophobic substrate in immersed solvent–supported microextraction as a novel strategy for determination of organic pollutants in water samples

    , Article Ecotoxicology and Environmental Safety ; Volume 163 , 2018 , Pages 104-110 ; 01476513 (ISSN) Baktash, M. Y ; Asem Yousefi, A ; Bagheri, H ; Sharif University of Technology
    Academic Press  2018
    In this research, a new approach for extraction and determination of polycyclic aromatic hydrocarbons from sea and rain water samples was developed by implementing a superhydrophobic substrate and consuming the least amount of solvent. This version of solvent–supported microextraction enabled us to perform the procedure in the immersion mode with the slightest troubles arising from water leakage into the gas chromatography. The superhydrophobic property leads to the fixation of extracting solvent on the substrate surface during water sampling. To prepare a superhydrophobic substrate, a piece of melamine foam was coated by tannic acid and silica nanoparticles using methyltrimethoxysilane and... 

    Immersed single-drop microextraction-electrothermal vaporization atomic absorption spectroscopy for the trace determination of mercury in water samples

    , Article Journal of Hazardous Materials ; Volume 165, Issue 1-3 , 2009 , Pages 353-358 ; 03043894 (ISSN) Bagheri, H ; Naderi, M ; Sharif University of Technology